Machine for removing insulation from the ends of wound armature wires



KIRSCH MACHINE FOR REMOVING INSULATION FROM THE ENDS 0F WOUND ARMATUREWIRES March 16, 1954 3 Sheets-Sheet 1 Filed May 6, 1948 IN V EN TOR.

ATTORNEY.

March 16, 1954 Q w sc 2,671,913

MACHINE FOR REMOVING INSULATION FROM THE ENDS OF WOUND ARMATURE WIRESFiled May 6, 1948 3 Sheets-Sheet 2 INVENTOR. Carl W Kirsch BY 52MATTORNEY.

March 16, 1954 2,671,913

C. W. KIRSCH MA NE FOR REMOVING INSULATION FROM ENDS OF WOUND ARMATUREWIRES 3 Sheets-Sheet 3 Filed May 6, 1948 INVEN TOR. Carl WlfirrchATTORNEY.

Patented Mar. 16, 1954 MACHINE FOR REMOVING INSULATION FROM ENDS OFWOUND ARMA- TURE WIRES Ga K ch, Canton, ilhic as igns to The HooverCompany, North Qanton, Ohio a gorporat ch of Ohio Application May 6,1948, Serial No. 25,461

13 Qlaiins. (01. 1521) "this in ention relat s o the manuie ur o mo ora; d mo e art u arly t ap ar u for and me hod r m vin t e insulation fom t e n s o a em ed armat e ire p e a tory to con e tin such ends to hco m e men s.

in t e ast it has bee the r i to individuai y str p h ins la ion m e ndsof as emhlesi armature w es by hand and to d clean the stripped ends,which procedure is slow, tedious, and costly. With some of the morereoentiy used insulating materials it is practically impossible toremove the ns l ti n t r imm by hand,

According to thi nvention he Wound armature is placed in a f xture andthe machine automatically separates the wire ends, removes theinsulation therefromand clean the wire.

More specifically according to this invention a plurality of armatureholding fixtures are r0- tatably mounted on an indexing carriage havinga plurality of work stations spaced thereahout. The arrangement is suchthat the carriage is periodically indexed so as to move the fixturessequentially from one station to the At the first station the woundarinatures are laced in the lower section of the fixture, at he se ond te en e se r ted nd end d ad al y o a l e t u per e of the lower fixturesection, at the third section the upper fixture section is placed on thelower so as to clamp the Wires between the mating edges of the sections,at the {fourth station the nsula n o th te din e ds i eherred hr theapplisa-t ion of an acetylene flame thereto,

At the f fth statio the charred insulation on ne Side 0. he e t din endss em and the wire cleaned by the application of the abrading aetion of awire or'similar brush, at the sixth station the radially extending endsof the wires are pushed upwardly to expose the other side of the wiresand at the seventh station the charred nsulation is removed from theother side of the extending ends and the wire cleaned by the abratli ngaction of a wire brush.

At the burning and abrading station the fig:- tures are rotated throughat least one revolution so that all of the wires are treated. Theindexing mechanism is so controlled that the rotation of the fixturesthrough one revolution will se t e a er o be indexe and h fi tu t he moed h m ne a io to he At the l a i wir c amp-i s and wi e turnin h tio thfi u e e st t o r A he wi e separating stat on the fixtu es re era ly 2rotatetl high s ee so that he i e are to their redia i n by centri ugalaceprdine to the roadest aspec o .6 sub: method acc to thi n on he e es9f the wires of a wound a mat a e nded into a rad l pos t on the inulation he eof the red by the application of heat and the, eher esinsulation. r moved to an ah as v ec 1 1 Accord n to h b oadest s ts ofanoth r subcombination according to this invention the tree of a woundarmatur a e se arat nd. ex en ed to a po tion exte din adia ly of t earma u e by en rifu al action While a ng th mature a hi h spee nd h ldinthe wi e soils in posit eh on the here of the e maturethe ob e t and ada t es o t i n ntime will heceme aoe ht as th d s ri ion re= needs whentak n in imeeti h wi the eee m panyihed a n s wh ch:

Eligure 1 is a plan yievvoj aportionof the maohineof this inventionshowing the indexing carriaee a d h dr v ng and i e i m ns o thecarriage and armature holding fixtures;

Figure 2 is a vertical sectional v ievvof the ma Qhine of this inventionincluding a section throughpne of the fixtures as it appears at the hurihe s ion;

Figu e 3 i a e s e t e i w o h m h n th in en on o n t tures a t eyappea at th va ou st ti ns Figure 4 is a vertical plan View of a fixtures it a e s a t e Wire tu n s i nd Fi ure 5 is a vertical plan view ofthe drive i-ng mechanism for the fixtures when positioned at the w e potionin tat on- Referring to the drawings and particularly to Fig. 1thereof, the working stations are indicated by the letters A to G,inclusive the station A being the loading and unloading station, B thewire separating and positioning station, C the wireclamping station, Dthe burning station, it the first ahrading station, F the wire turningstation and G the second abrading station.

The-machine comprises a suitable supporting tra ne- IJ} rotatahl-ycarrying a main spindle H which in turn carries the indexing carriage12. The indexing carriage i2 rotatably carries a plurality of fixtures(at least one for each active station) generally indicated at l3 equallyspaced a ou :iBBPQ i hQ Y-Q the car a e 1'12 fi ture it comprise a ve tcal in I4 rotatably supported in bearings |5 near the edge of thecarriage l2. Integral with the spindle I4 is a lower fixture section l6adapted to snugly receive a wound armature with the upper edge of thecore adjacent to the upper edge of the lower fixture section |6 so thatthe free ends I 8 of the armature wires can be extended outwardly overthe free edges thereof, An upper fixture section I9 is adapted toreceive the commutator end of the armature I1 and has an opening 29 toreceive the end of the armature shaft so as to rigidly hold the armatureH within the fixtures l3. The mating edges of the lower section l6 andthe upper section 9 have provisions for leading the wire ends I8radially outwardly between the mating edges of lower section l6 andupper section I9. A pulley 2| is rigidly attached to the lower end ofeach spindle |4.

Rigidly attached to the main spindle II is an indexing ratchet wheel 22which cooperates with an indexing arm 23 pivoted to the spindle andhaving a pawl 24 held in engagement with the teeth of the ratchet wheel22 by a spring 25. The spindle H and correspondingly the carriage I2 isnormally held against rotation by a pin 26 (Fig. 2) engaging in one ofthe plurality of openings 21 in the indexing wheel 22 and is heldagainst reverse rotation when the pin 26 is released by a pawl 28carried by the frame l and engaging the ratchet teeth of the indexingwheel 22.

Connected to the indexing arm 23 by means of a link 29 is the end of apiston rod 39, the piston 3| of which is adapted to reciprocate in acylinder 32 suitably supported by the frame Ill. The end 33 of thecylinder is connected by a conduit 34 to a suitable control valve 35.The end 36 of the cylinder 32 is connected to the control valve 35 by aconduit 31. The control valve 35 is connected to a source of air underpressure by a conduit 38 and to a bleeder valve 39 by conduits 40 and4|. The arrangement is such that when the bleeder valve 39 is in theposition shown in Fig. 1 there is a reduced pressure in the end 36 ofthe cylinder 32 and the p st n 3| is held in the position shown inFig. 1. When the valve actuator 42 is pushed to the right the pressureis raised in the end 36 of the cylinder 32 and reduced in the end 33 sothat the piston 3| will be forced to the opposite end of the cylinder 32to that shown in Fig. 1. Any type of valves 35 and 39 may be used whichwill produce the above result.

The fixture 3 are adapted to be rotated at stations D, E, and G by amotor 43 driving an endless belt 44 by means of a belt gearing 45,reduction gearing 46 and pulley 41. The belt 44 is threaded over thepulleys 2| at the stations D, E, and G, over the pulley 41 and over theidler pulleys 48, 49, and 50 suitably supported by the frame In. Thepulley 41 is preferably of the same diameter or slightly larger than thepulleys 2| so that the fixtures l3 at the stations D, E, and G will berotated at least once for each revolution of the pulley 41.

Rigidly secured to the shaft of the pulley 41 is cam wheel having cams52 and 53 thereon. Cam 52 actuates the operator 42 of the bleeder valve39 and the cam 53 actuates an on-ofi switch 54 adapted to energize anddeenergize a solenoid 55 connected to the pin 26.

At the station B the pulley 2| is adapted to engage a friction wheel 58(Fig. 5) driven by a high speed electric motor 59, pivotally secured tothe frame l0 by an arm and spring-biased against a stop 6| by a spring62. The arrangement is such that as the fixtures l3 are indexed to thestation B the friction wheel 58 will engage the pulley 2| under thepressure of spring 62.

Preferably the motor 59 rotates continuously when the machine is inoperation but a separate control switch may be provided. The motor 59may also if desired be automatically energized upon the engagement ofthe friction wheel 58 with the pulley 2|. For example, an on-ofl switchcould be actuated by the movement of the arm 60 as the wheel 58 engagesthe pulley 2|.

At the station D are a plurality of acetylene burners 63 and 64positioned above and below the wire ends I8 as shown in Fig. 2. Atstation E is a rotating Wire brush 65 which is continuously rotateddownwardly in the direction of the arrow as indicated in Fig. 3. Atstation F a cam 66 (Fig. 4) suitably supported on the frame |0 engages apin 61 carried by the plate 68 connected by rods 69 to a sleeve 70slidably mounted about the lower fixture section |6 for a purpose whichwill be described presently. At station G is a brush H which iscontinuously rotated upwardly as shown by the arrow of Fig. 3. Thestation H is idle but the fixture I3 is being rotated. If desired thefixture could be made stationary at this station and it could then bemade the unloading station.

Positioned to engage the top of the upper fixture section I9 at thestations E, F, and G are cam plates 12 and 13 which automatically engagethe top section l9 as the carriage I2 is indexed to tightly hold thesections l9 and I6 together so that the wire ends |8 will be tightlyclamped. The plates 12 and 13 may be fixed to the frame I!) in anysuitable manner.

Operation A wound armature I1 is placed in the lower fixture section l6at station A and the motor 43 started which will cause the pulley 41 torotate in unison with the fixtures |3 at the stations D, E, and G. Thecam 52 will eventually engage the operator 42 for the bleeder valve 39so as to increase the pressure in the end 36 and decrease it in the end33 of the cylinder 32 causing the piston 31 to move to the left and movethe indexing arm 23 counter-clockwise as viewed in Fig. 1. Shortly afterthe engagement of the cam 52 with the actuator 42 the cam 53 will engagethe actuator for the switch 54 to energize the solenoid 55 and withdrawthe pin 26 from the opening 21 in which it is then positioned to freethe carriage l2 for indexing movement. During the counterclockwisemovement of the indexing arm 23 the pawl 24 will ride freely over theteeth of the indexing wheel 22 since the wheel is held againstcounter-clockwise movement by the pawl 28.

As the cam 52 rides free of the control arm 42 of the bleeder valve 39,high pressure will be reestablished in the end 33 of the cylinder 32 andthe end 36 will be vented to low pressure. This will cause the piston 32to move to the right and move the indexing arm 23 clockwise as viewed inFig. 1. The pawl 24 will engage the teeth of the indexing wheel 22 andindex the carriage l2 so that the fixture containing the wound armaturewill be moved to station B. By this time the cam 53 will have disengagedthe control of the switch 54 to deenergize the solenoid 55 whereby thepin 26 which is spring-biased upwardly will snap into the next aperture21 as the fixture reaches the station B so as to rigidly lock thecarriage l2 against movement.

As the fixture l3 approaches station B the pulley 2! will engage thefriction wheel 58 and pivot the motor 59 counterclockwise as viewed inFig. 1 against the bias of spring 62 until the wheel 58 and pulley 2|are in good driving relationship with each other. This will cause thearmature I! to be rotated rapidly so that the wire ends it will beseparated and moved to a radial position overlying the upper edge of thelower fixture section It by centrifugal action. This result is shown atstation E in Fig. 3.

It is to be understood that it is within the concept of this inventionto move the wire ends l8 into their radial position by hand at station Bbut it is preferable that this be done by centrifugal action as abovedescribed.

During the movement of the wire ends 58 to the radial position the camwheel 5! has been contlnuously rotating and eventually will render theindexing mechanism operable to index the carriage l2 another step tobring the fixture I3 with the armature I'E therein to the station C. Atthe station C the upper fixture section is is merely placed over thecommutator end of the armature l1 so as to position the wire ends 48between the mating edges of the fixture sections it and Hi.

Th cam wheel 5| will again render the indexing mechanism operative andthe carriage [2 will again be indexed to bring the fixture with thewires extending through the walls to station I). As the pulley 2!approaches station D it will engage the endless belt 4 3 so that thefixture i 3 will be rotated in unison with the cam wheel 5 i. will bringthe wire ends it with the insulation thereon into the flames from theburners E3 and 8:3. As the fixture i3 is rotated the insulation on bothsides of one after the other of the wire ends it will be charred. Duringthis action the fixture i3 will protect the insulation of the main partof the windings of the armature H from the heat of the flame so thatonly the insulation on the extending ends 18 will be charred. By thetime the fixture l3 at the station D has made one complete revoture isalso rotating in unison with the cam wheel 5|. The continuously rotatingbrush 65 will brush the wire ends it downwardly against the lowersection it of the fixture I3, one after the other as the fixture i3 isrotated. The abrasive action of the wire brush 65 will remove thecharred insulation from the top side of the wire ends 18 and will cleanand polish the metal of the wires. By the tim the fixture It has made acomplete revolution at station E the cam wheel 55- will.

again cause the indexing mechanism to operate and move the fixture tostation F where the wire ends l8 are still tightly clamped between thefixture sections by reason of the engagement of the top section L! withthe plate 72.

As the fixture leaves the station E the pulley 2i will disengage fromthe belt 44 so that the fixture will be stationary as it approaches andleaves the station F. Also as the fixture it approaches the station Fthe pin 5? will engage the cam 5t and raise the sleeve Til upwardlyabout the lower section [6 of the fixture l3 so as to bend the wire endsI 8 upwardly against the top section it. The cam wheel 5| will againcause the indexing mechanism to operate and move the fixture to stationG. As the fixture leaves the station F the pin. 61 will ride over thecam 66 and the sleeve 70 will return to its downward position.

As the fixture l3 approaches station G the pulley 2| will again comeinto contact with the belt 44 and the fixture will be rotated at stationG. The wire brush II will sweep upwardly over the lower sides of thewire ends l8 and brush them against the upper fixture section I9. Theabrasive action of the brush II will remove the charred insulation fromthe lower sides of the wire ends 18 and clean the metal of the wire, oneafter the other as the fixture I3 is rotated as shown at station G ofFig. 3. At station G the wire ends are tightly clamped by the engagementof the upper section IS with the plate 13.

The indexing mechanism will continue to operate periodically until thefixture 3 with the stripped armature thereon again reaches the stationA. The attendant then removes the stripped armature and replaces it withan unstripped one.

While in the above description, for reasons of clarity, the operationhas been described in con nection with a singl fixture advancingstep-bystep from station to station, the actual operation of the machineis continuous. As soon as one fixture It leaves station A another ismoved into position and an unstripped armature is placed therein. Whenall of the fixtures are loaded the machine will be operatingsimultaneously at each station above described and the attendant willhave to continuously remove a stripped armature at station A and replaceit with an unstripped one.

From the foregoing it can be seen that this invention provides anapparatus and method whereby the insulation may be continuously strippedfrom the free ends of the wires of an as sembled armature and the wirescleaned and polished automatically without manual operation except theloading and unloading at station A and the placing of the upper fixtursection I9 over the armature at station C.

While I have shown but a single modification of my invention it is to beunderstood that this modification is to be taken as illustrative onlyand not in a limiting sense. I do not wish to be limited to theparticular structure and method shown and described but to include allequivalent variations thereof except as limited by the scope of theclaims.

I claim:

1. A machine for removing the insulation from and cleaning the ends ofassembled armature wires preparatory to securing the ends to thecommutator segments comprising; a table rotatably mounted about avertical axis; said table carrying a plurality of rotatable spindlesarranged annularly near'its periphery; a fixture for receiving a woundarmature carried by each of said spindles; said fixtures including ahousing to house the entire wound armature with the ends of the wiresprojecting through the walls of said housing; a plurality of operatingstations spaced about the periphery of said table including a loadingstation, a burning station where the insulation on the ends of the wireis charred both above and below, a first brushing station where thecharred insulation is removed from thetopof the ends of the wires, awire bending station where the wires are bent upwardly to expose thelower sides of the ends of the wire and'a second brushing station wherethe charred insulation is removed from the under side of the ends of thewire; said stations being arranged in the order named; means forrotating the spindles positioned at the burning station and. at bothbrushing stations, and means rendered operable upon rotation of saidspindles through at least one revolution of said spindles for indexingsaid table about its axis to move said spindles from one station to thenext.

2. A machine for removing the insulation from and cleaning the ends ofassembled armature wires preparatory to securing the ends to thecommutator segments comprising: an indexing carriage; a plurality ofrotatable spindles carried by said carriage; a fixture for receiving awound armature carried by each of said spindles; each of said fixturesincluding a housing including a cover to enclose an entire woundarmature with the ends of the wires projecting through the walls of saidhousing; a plurality of operating stations spaced about the periphery ofsaid carriage including a loading station, a wire separating station atwhich the ends of the wires are moved to a position extending radiallyof the armature, a station at which the cover for said fixture is placedover the armature, a burning station where the insulation on the ends ofthe wires is charred, a first abrading station where the charredinsulation is removed from one side of the wire ends and the endscleaned, a wire bending station where the wires are bent to expose theother side of the wire ends and a second abrading station where thecharred insulation is removed from the other side of the wire ends andthe ends cleaned; said stations being arranged in the order named; meansfor rotating said spindles at the burning station and at both abradingstations, and means rendered operable upon the rotation of said spindlesthrough at least one revolution of said spindles for indexing saidcarriage to move said spindles from one station to the next.

3. A machine according to claim 2 including means for rapidly rotatingsaid spindles when positioned at said wire separating station to movethe wire ends to their radial position by centrifugal action.

4. A machine for removing the insulation from and cleaning the ends ofassembled armature wires preparatory to securing the ends to thecommutator segments comprising; an indexing carriage; a plurality ofarmature receiving fix tures carried by said carriage; a plurality ofoperating stations spaced about the periphery of said carriage includinga wire separating station where the wires are moved to a, positionextending radially of the armature, a burning station where theinsulation of the wire ends is charred and a plurality of abradingstations where the charred insulation is removed from the wire ends andthe wire ends cleaned, means for rotating said fixtures at said burningand abrading stations, and means rendered operable upon the rotation ofsaid fixtures through at least one revolution thereof for indexing saidcarriage to successively move said fixtures from one operating stationto the next.

5. A machine according to claim 4 including means for rapidly rotatingsaid fixtures at said wire separating station to separate the wire endsby centrifugal action.

6. An apparatus for removing the insulation from and cleaning theprojecting ends of assembled armature wires preparatory to securing theends to the commutator segments comprising; a rotatable carriage; anarmature receiving fixture rotatably carried by said carriage; a wireseparating station, a wire clamping station, a burning station, a firstabrading station, a wire bending station and a second abrading stationpositioned about said carriage in the order named; means for rotatingsaid carriage to bring said fixtures successively to each of saidstations; means at said wire separating station for rapidly rotatingsaid fixture to separate said ends by centrifugal action so that theyproject outwardly from said fixture; said fixture including a protecting and wire clamping cap to be applied at said wire clampingstation; means at said burning station for charring the insulation onsaid projecting ends and for rotating said fixture to bring saidprojecting ends progressively past said charring means; means at saidfirst abrading station for applying a clamping pressiu'e to said cap,applying a downward abrading action to the top side of said projectingends and for rotating said fixture to successively bring said projectingends beneath said abrading means; means at said wire bending station formaintaining said clamping pressure to said cap and for bending saidprojecting ends upwardly against said cap; and means at said secondabrading station for maintaining said clamping pressure to said cap, forapplying an upward abrading action against the lower sides of saidprojecting ends and for rotating said fixture to successively bring saidprojecting ends beneath said abrading means.

7. A machine for removing the insulation from and cleaning the ends ofassembled armature Wires comprising, an indexing carriage, a pluralityof rotatable armature holding fixtures arranged in a circle adjacent theperiphery of said carriage, said fixtures including a bottom portionformed to support a wound armature with.

its axis positioned vertically and with the loose wire ends positionedabove the top thereof. a.

said spindles at certain other stations includ-- ing said wireseparating ttation, means for indexing said carriage so as to move saidfixtures sequentially from one station to another, and means for rapidlyrotating said fixtures at said wire separating stations at a speedsufficient to separate the loose ends of the wires by centrifugalaction.

8. A machine according to claim '7 in which the station following saidwire turning station is a clamping station and said fixture includes atop portion shaped to engage the top edge of said bottom portion andclamp the separated ends of the wires between the top and bottomportions, and said top portion being applied at said clamping station.

9. A machine according to claim 8 in which said fixtures include a lowerrotatably mounted cup-shaped member, and an upper inverted cupshap edmember having its open edge mating with the open edge of said lowercup-shaped member, said upper cup-shaped member being shaped to receivethe commutator end of a wound armature and said lower cup-shaped memberbeing shaped to snugly receive the opposite end of the wound armaturewith the mating edges of said members positioned adjacent the commutatorof the armature.

10. A machine for removing insulation from the ends of assembledarmature wires comprising, an indexing carriage, a plurality ofrotatable armature holding fixtures arranged in a circle adjacent theperiphery of said carriage, said fixtures including a bottom portionformed to support a wound armature with its axis positioned verticallyand with the loose Wire ends positioned above the top edge thereof, aplurality of work stations including a wire separating stationpositioned about the periphery of said carriage, gearing means arrangedto rotate said fixtures at a. comparatively slow rate at certain only ofsaid stations and to cease rotating them at certain others of saidstations including said wire separating station, means for indexing saidcarriage so as to move said fixtures sequentially from one station toanother, means for locking said carriage against indexing movement,means for simultaneously releasing said locking means and initiating theaction 01 said indexing means, and means for rapidly rotating saidfixtures at said wires separating station at a speed sufiicient toseparate the loose ends of the wires by centrifugal action.

11. A machine according to claim 19 in which said fixtures include alower rotatably mounted cup-shaped member, and an upper invertedcupshaped member having its open edge mating with the open edge of saidlower cup-shaped memoer, said upper cup shaped member being shaped toreceive the commutator end of a wound armature and said lower cup-shapedmember being shaped to snugly receive the opposite end of the armaturewith the mating edges of said members positioned adjacent the commutatorof the armature.

12. A machine for removing the insulation from and cleaning the ends ofassembled armature wires preparatory to securing the ends to thecommutator segments comprising; an indexing carriage; a plurality ofarmature receiving fixtures rotatably mounted in a circle adjacent theperiphery of said carriage; said fixtures including a bottom portionformed to support a wound armature with its axis positioned verticallyand with the loose wire ends positioned above the top edge thereof; aplurality of operating stations spaced about the periphery of saidcarriage including a wire separating station where the wires are movedto a position extending radially of the armature, a burning stationwhere the insulation or the wire ends is charred and a plurality ofabrading stations where the charred insulation is removed from the wireends and the wire ends cleaned; means for rotating said fixtures at a,comparatively slow rate at said burning and a'brading stations and at arapid rate at said wire separating stations sufficient to move the loosewire ends outwardly by centrifugal action; and means rendered operableupon the rotation of said fixtures through at least one revolutionthereof for indexing said carriage to successively move said fixturesfrom one operating station to the next.

13. A machine according to claim 12 in which said fixtures include arotatably mounted lower cup-shaped member, an upper inverted cupshapedmember having its open edge mating with the open edge of said lowercup-shaped member, said upper cup-shaped member being shaped to receivethe commutator end of a wound armature and said lower cup-shaped memberbeing shaped to snugly receive the opposite end of the armature with themating edges of said members positioned adjacent the commutator of thearmature.

CARL W. KIRSCH.

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